Priority is claimed on Japanese Patent Application No. 2004-062386, filed Mar. 5, 2004, the contents of which are incorporated herein by reference.
1. Field of the Invention
The present invention relates to a follow running control system for performing follow running control in which a preceding vehicle is determined to be a target vehicle to be followed by the present vehicle.
2. Description of Related Art
In a known follow running control system, in order to reduce the labor in driver operation, a inter-vehicle distance sensor for determining the distance between the present vehicle and the vehicle in front (i.e., the preceding vehicle) is provided for controlling the running state of the present vehicle so as to ensure a specific distance between vehicles, thereby performing advancing, stopping, and running operations while following the preceding vehicle (see, for example, Japanese Unexamined Patent Application, First Publication No. H10-147160).
Such a follow running control system may have a communication device for communicating the advance of the preceding vehicle while the present vehicle waits for a signal at the intersection or stops on a congested road, and for urging advancing of the present vehicle. In this case, even when the road is crowded with a number of vehicles, a burden on the driver for paying attention to the forward direction is reduced, and the driver is relieved of complicated operations such as repeatedly advancing and stopping again and again.
In conventional systems, driving operation by the driver of the present vehicle for advancing the vehicle is not effective until detecting the advance of the preceding vehicle. Therefore, a difference in driving sensation is produced between running by the driver's manual operation and follow running by the follow running control system, so that the driver may experience discomfort.
More specifically, in detection of the advance of the preceding vehicle, the distance to the preceding vehicle or a change in relative speed with respect to the preceding vehicle is determined by referring to signals of a radar or the like for detecting the preceding vehicle; thus, advancing of the preceding vehicle cannot be detected until the preceding vehicle has actually advanced. However, the driver can recognize situations in which the signal in front is changed from red to green and thus vehicles can advance or that another vehicle in front of the preceding vehicle has been advanced. Therefore, the driver can judge that the preceding vehicle is just about to start moving and can start to release the brake pedal. Accordingly, a difference in driving sensation is produced between running by the driver's natural operation and follow running by the follow running control system.